Table of contents

Back to the main page 1. Compute Background Evolution 2. Compute Recombination History 3. Compute Perturbations 4. Compute Powerspectrum

Compute Recombination History

Here you can select the cosmologically parameters and numerically compute the recombination history in $\Lambda$CDM and make some plots. NB: For Helium we use the Saha approximation and for Hydrogen we use the Peebles equation. For reionization we use the $\tanh$ model that is standard in CAMB and CLASS. The results using the fiducial parameters below can also be found here.

Background parameters

Hubble parameter ($H_0\equiv 100 h{\rm km/s/ Mpc}$):
Baryon density:
CDM density:
$\Omega_{\rm CDM}$:
Curvature density ($\Omega_k \equiv -k/H_0^2$):
Temperature of the CMB today ($\Omega_\gamma \propto T_{\rm CMB}^4 / h^2$):
$T_{\rm CMB}$ (K):
Effective number of neutrinos ($\Omega_\nu \equiv N_{\rm eff}\frac{7}{8}\left(\frac{4}{11}\right)^{4/3}\Omega_\gamma$):
$N_{\rm eff}$:
Dark energy equation of state (CPL parametrisation) $w = w_0 + w_a(1-a)$:

Recombination parameters

Primordial helium (mass) abundance:
Include Reionization:
Reionization (H and He) redshift:
$z_{\rm reion}$:
Reionization (H and He) redshift width:
$\Delta z_{\rm reion}$:
Include He+ Reionization:
He+ reionization redshift:
$z_{\rm HeReion}$:
He+ reionization redshift width:
$\Delta z_{\rm HeReion}$:
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